NEWSLETTER    Vol. 01/ 2010, February

Autologous Chondrocyte Implantation Using the Original

Peristeum-Cover Technique Versus Matrix-Associated Autologous

Chondrocyte Implantation

- A Randomized Clinical Trial -

Felix Zeifang, MD, Ph.D et al.; available online link to the paper

We would like to introduce the most recent publication by Zeifang et al. published in The American Journal of Sports Medicine in 2010.

The paper reports on a randomized clinical trial comparing BioSeed^®-C as an unique three-dimensional chondrocyte graft with mechanical and shape stability versus first generation ACI with periost technique in terms of clinical safety and efficacy.

In this randomized study a total of 21 patients with symptomatic isolated full-thickness cartilage defects of the femoral condyle were treated with BioSeed^®-C or first generation ACI with periost technique. For evaluation of cartilage repair, Magnetic resonance imaging (MRI) was performed and scored by the Magnetic Resonance Observation of Cartilage Repair score (MOCART) for up to 24 months after surgery. Additionally, the postoperative  change in knee function was assessed by the International Knee Documentation Committee score after 3, 6, 12 and 24 months for primary outcome.  Secondary outcome parameters were postoperative changes in health-related quality of life, knee functionality and physical activity.

6 months after surgery, MRI results of the BioSeed^®-C group showed a significant lower MOCART score, corresponding to more normal diagnostic findings. 12 and 24 months postoperatively, clinical results showed further improvement of patients with no significant difference. Assessment of postoperative changes like knee function, quality of life or physical activity also showed no significant difference over this observation period.

Regarding safety aspects, in patients treated with the first generation ACI with periost technique one transplant delamination was  observed and one osseous spur developed after surgery. In the BioSeed^®-C group one patient developed an osteochondral lesion. Transplant hypertrophy occurred frequently and was more common in the first generation ACI with periost technique group, but was not associated with symptoms. Moreover, there were no cases of infections, allergic, toxic or autoimmune reactions or malignant transformation in both treatment groups.

The authors conclude that BioSeed^®-C is a safe and effective method for cartilage regeneration, showing good clinical results at an early stage as assessed by MRI. Compared to first generation ACI with periost technique, the BioSeed^®-C technique avoids an additional periost outtake and thereby minimizes patients discomfort and operation time. Additionally, the use of this unique three-dimensional chondrocyte graft also provides an easier handling for the surgeon and ensures mechanical and shape stabilty of the transplant during operation procedure.

In particular, the immobilization of the chondrocytes within the matrix of BioSeed^®-C allows for treating cartilage defects that lacks an intact cartilage rim surrounding the defect. This opens the avenues for treating degenerative focal osteoarthritic cartilage defects as recently shown by Kreuz et al. 2009 (see Newsletter vol. 2/2009). Beside the treatment of chondral defects of the knee joint, the application of BioSeed^®-C is also indicated for osteochondral defects.